Antisiphon device for fuel tanks



Oct. 17, 1933.

F. E. TERRY ANTISIPHON DEVICE FOR FUEL TANKS Filed Aug. 22, 1932 n m A :0 T w a I, IWJ F 9 Z Patented Oct. v17, 1933 UNITED STATES PATENT, osncs ANTISIPHON nnvrcn son FUEL TANKS Floyd E. Terry, Lancaster, Ohio Application August 22,1932. Serial No. 629,970 3 Claims. (01. 220-86) The invention relates to means for preventing theft of liquid fuel from the filling openings of fuel tanks on motor vehicles, and more particularly to a fitting adapted to prevent the siphoning 6 of fuel from such tanks by removal of the filler cap, and insertion of a s'iphon'tube, which'is a common source of loss to motorists. It is a special aim to present this fitting in a form that may be attached without the use of any tools-by perl sons without mechanical training or ability, as an addition to the standard tanks of common construction now generally in use. The fitting is adapted to be incorporated as standard equipment on original construction in such tanks, but itis a particular aim to enable its attachment to tanks with the old styles of fittings'upon which a cap is arranged to be screwed by an interrupted thread device, or other common means. It is a further object to present a construction including means to prevent removalof the appliance after emplacement.

It is a further important object to embody the device in such manner that while attaining the theft prevention, it will also operate to enable more ready fiow of fuel through the filling openings of tanks equipped with the invention, by preventing the back pressure of escaping air and main large duct, while the escaping air and vapor is permitted to pass outwardly of this duct for the most part, and is prevented from obstructing 3'5 the entrance of fuel in such manner as to cause spilling thereof outside the tank, which is a common experience of motorists and a source of considerable loss of fuel.

Additional objects, advantages and features of invention reside in the construction arrangement and combination of parts involved in the embodiment of the invention, as may be understood from the following description and accompanying drawing, in which Fig. 1 is a vertical section of the preferred bodiment of the invention,

Fig. 2 is a cross-section on the line 22 of Fig. 1,

' Fig. 3 is an elevation of the fitting alone,

Fig. 4 is a section on the line 4--.4 of Fig.1. Fig. 5 is a view similar to Fig. 1 showing the device adapted to use where gooseneck fittings :are incorporated on tanks to which my invention is to be attached. I v

' There is illustrated a tank 10 having the usual filling opening 11 and welded to the tank there mouth fitting.

is a filler mouth fitting 12 having an upper intumed and recurved edge portion, in which at two or more points there are formed slots 13 adapted to receive the usual lateral spur or 111330! the common filler cap of the fuel tank. From each .0 slotnear its upper part an-inclined slot or edge 14 is extended spirally downward to the inner lower edge of the recurvededge of the mouth fitting. The ordinary filler cap is provided-with a number of lateral lugs corresponding to the num-- her-of the slots in the mouth fitting, and when the cap is presented, one of the lugs entering through each slot, turning of the cap will cause the lugs to wedge upon the inclined edges 14', drawing the cap tight against the top edges of the My invention comprises a cylindrical body por tion 15 of a diameter to enter through the standard mouth fitting 12 and to rotate therein without obstruction. The upper part or mouth 16 of this body is enlarged and formed as nearly aspossible as a duplicate of the mouth of the fitting 12, so that the usual filler cap may be engaged therewith the same as it would be with the, original mouth fitting 12. o

In addition a further enlargement or flange .17 is formed at the lower part of the mouth enlargement, its edge portion being downturned to partly enclose the edge of the mouth fitting, and on the body portion 15 immediately below the flange 1'! lugs 18 are formed integrally, corresponding to the lateral lugs of the standard filler cap.

It will be seen that, the standard cap being removed from the mouth fitting 12, the lower body portion 15 may be inserted in the ordinary 9 mouth fitting 12,.and the lugs 18 engaged through the slots 13 and against the inclined edges 14 of the fitting 12'to hold my attachment snugly in the filling opening of the tank. The regular cap may then be engaged with the upper part of my device, as willbe understood.

In order to make engagement of. my device permanent, and make it impossible to remove the device without destroying the standard mouth fitting 12 with which my device is engaged, I have provided on the sides of the body 15 springs 19 corresponding in number to the number of lugs 18, adapted to engage in the slots 13 after my device has been turned to engage the lugs 18 propin the regular filling opening, the springs will be pressed inward by the edges of the mouth of the fitting 12, and when my attachment is rotated to bring the spring adjacent the slots 13 the springs will move outwardly through the -'-slots 13. The springs are made of a width to snugly fit the slots 13, and of a sufficient thickness to afford the necessary resistance to turning of the attachment after the springs are once engaged in the slots 13.

The body portion 15 is preferably of such length that its lower extremity lies closely adjacent or above the top level of fuel in the tank to which my attachment is applied. Formed integrally with the cylindrical wall portion 15 of the body there are three sets of interior grille bars 20, 21, and 22, respectively, arranged one above the other, at three levels. The bars of the upper and lower sets 20 and 22 are alined vertically, while those in the intermediate set 21 are staggered with the others, so as to aline with the spaces between the adjacent sets of grille bars. The upper and lower grilles in the present instance consist of three bars, the outer bars in each set being spaced from the laterally adjacent wall of the body 15. There are but two bars shown in the intermediate set, and the spaces 23 at each side of the sets 20 and 22 are overlain by tongues 24 projected inward from the wall of the body 15, openings 25 being formed through the wall immediately above the bases of the tongues, so that these tongues have their upper ends on a level with the upper sides of the openings 25. The tongues are projected inwardly sufliciently to lie respectively in close relation to the adjacent planes of the bar sets 20-and 23.

It will be seen that with my attachment engaged with the filler fitting 12 of a tank, after removal of the cap of the usual kind, it will be impossible to introduce a satisfactory siphon device, to draw off fuel, because the bars 20, 21 and 22 are above the normal or mean level of the fuel, and the spaces between the bars 20 and 21, and between the bars 22 and 23 and the tongues 24 are too narrow to admit passage of a proper tube .-for the purpose of drawing off any of the fuel. It should be noted that the vertical distance between mutually adjacent grilles is less than the spacing between the bars of each grille, so that if a small tube should be entered between the bars of the top grille, it could not be properly deflected to pass diagonally between the bars of one grille and those of another.

It will be noted that with my device engaged with the ordinary filler fitting 12 as shown in Fig. 1, a substantial annular space 26 is formed around the body 15 of my device within the fitting 12, and extending to the top of the latter. The openings 25 are all located below the top of the fitting 12, and when fuel is to be introduced into the tank equipped with my invention, air and vapor is afforded a free passage through the space 26 and openings25 to theupper part of the passage through the body 15. The openings 25 may be in two vertically spaced sets as shown, or more, and the uppermost ones open into the large clear passage 27 through the body 15 above the uppermost grille 20. From this point air seeking escape through the device may do so with less obstruction or tendency to block or throw out the fuel. In fact, where nozzles are used to fill or supply fuel to the tank, the mouth of the nozzle will be below the upper openings 25, and air can therefore escape without encountering any fuel. Air seeking escape through the lower part of the body 15 from the lower end, will be opposed by a greater mass of fuel, and the tendency to form a large bubble or to move backwardly a large mass of fuel is greater where such air must move through the entire body of entering fuel than where air is admitted through the upper part of the passage for fuel.

For use of my invention in situations where the body portion 15 can not be extended into the mouth fitting of the tank, I have shown a construction in Figure 5 in which an extremely small or short tubular part 15' corresponding to the body 15 is provided, having the lugs 18 on the sides as before described, but spaced from the lower end of the part 15 only a short distance. The body wall or tubular part 15' extends above the lug only to a height corresponding to the level of the tip of the mouth fitting 12 when the lugs 18 are fully engaged with the edges 14 to wedge therewith. The part 15 is provided with a horizontal lateral flange 28, adapted to lie on the top edge of the gooseneck fitting 29 or other of some of the tank outlets which have to' be provided in some instances, extending a considerable distance horizontally and then being turned upward and formed with the mouthformation necessary to eriable the securement of the filler cap. The outer edge of the flange 28 has a downward extension to enclose-the end of the gooseneck or such other outlet as may be involved. i

From the flange 28 a large cylindrical wall 30- is extended upwardly with a diameter greater than that of the part 15' and approximately the same as that of the part of the gooseneck 29 within the downward extension of the flange 28. This wall 30 is extended to such height as desired to properly accommodate the nozzles of fuel conveying hose, or the mouths of funnels, and at its upper extremity is inturned and recurved, the recurved parts being slotted and shaped to provide the slots 13 and inclined edges 14 to be en-; gaged by the lateral lugs of the filler cap.

In the lower tubular part 15' two sets of grille bars 31 and 32 are provided corresponding to those 21 and 22 first described, and spaced the one set above the other in very close relation as at 33. While formed integrally with the wall 30 and extending across the space within the wall 30in longitudinal alinement with the spaces. between the bars of the upper grid 31, there is a top set of grid bars 34 spaced above the grid 31 the same distance as that between the grids 31- and 32.

In this device also, springs 19 are provided on the sides of the tubular part 15', and lugs 18 spaced circumferentially therefrom and at a suitable level to engage in the standard outlet fitting of motorvehicle fuel tanks, as before described.

In the use of my invention the appliances-of both Figure 5 and Figure 1 may be engaged permanently and safely against removal by simple manipulation which'any ordinary person is capable of carrying out, it being only necessary to remove the ordinary filler cap, insert the lower end of my attachment, and give it a partial rotation to bring the springs 19 into the slots 13, and then to engage the filler cap without change with the top of my attachment.

To introduce fuel through my attachment, the filler cap being removed, the fuel supply nozzle now generally used at dispensing stations may be inserted in the upper end of my attachment and the fuel pumped or allowed to enter as usual with the ordinary tank fittings. The fuel is permitted to move in the main longitudinally through the attachment, with immaterial deflection or impedance, and air and vapor leaving the tank is permitted to readily escape through the openings 25, as provided, as well as through the grilles themselves. My invention causes less obstruction than a screen of ordinary form, and is not intended to serve as a screen, although it will prevent large particles from entering the tank The device may be made of various materials found suitable, and may be cast or stamped or drawn by approved methods. As so farproduced, it has been cast of aluminum in one piece. The proportions of the various parts, and other details may be modified within the scope of the claims in many ways, and I do not regard the invention as restricted to the exact structure shown.

The attachment may be connected to inlet fittings of various forms other than those here shown, and other types of fastenings employed, and may also be modified in accordance with familiar or other approved practice to adapt it to be incorporated as an original fitting secured directly to the tank, by any usual fastening means.

I claim:

1. A tank fitting of the character described comprisim a duct element, a plurality of grilles spaced longitudinally in clou relation therein,-

each grille comprisingparallel bars, the bars of each grille being staggered with respect to those of the next adjacent grille, a lateral closure flange formed circumferentially on the exterior of the duct, a plurality of lateral lugs on the duct below the flange, and a yielding projection on the duct below the flange of a size and shape to engage slots of a filler fltting.

2. The structure of claim 1 in which the lugs are spaced longitudinally of the duct from the flange and said yielding projection comprises a locking member having its locking portion nearer the flange than the lugs and spaced. circumferentially from the lugs.

3. The structure of claim 1 in which the lugs are spaced from the flange, and said yielding proiection consists of a resilient yielding locking member having its locking portion nearer the flange than the lugs and spaced circumferentially from said lugs, the top of the duct having an enlargement with interior bayonet slot formations thereon to coact .with lugs of a closure arranged to correspond to the first named lugs.

FLOYD E. TERRY. 

